The present invention relates a process for culturing isolates of Antrodia camphorata to provide a product useful in medical and nourishment fields. The present invention also relates to a novel isolate of Antrodia camphorata, the culture of which exhibits pharmacological activities when the isolate is grown in a suitable medium.
Antrodia camphorata [(Zang and Su) S.-H. Wu, Ryvarden and T. T. Chang], also known as xe2x80x9cniu-chang-chihxe2x80x9d or xe2x80x9cniu-chang-kuxe2x80x9d in Taiwan, was recently reported as a new fungus species characterized by the cylindrical shape of its basidiospores appearing in fruit bodies, weakly amyloid skeletal hyphae, bitter taste and light cinnamon resupinate to pileate basidiocarps, as well as chlamydospores and anthroconidia in pure culture. The growth of this new fungus species is extremely slow and restricted to an endemic tree species, Cinnamomum kanehirai Hay (Lauraceae), as the only host. The detailed characterization and taxonomic position of A. camphorata were described in Chang, T. T. et al., Antrodia cinnamomea sp. nov. on Cinnamomum kanehirai in Taiwan, Mycol. Res. 99(6): 756-758 (1995) and Wu, S.-H., et al., Antrodia cinnamomea (xe2x80x9cniu-chang-chihxe2x80x9d), New combination of a medicinal fungus in Taiwan, Bot. Bull. Acad. Sin. 38: 273-275 (1997), the entire disclosure of which is incorporated herein by reference.
In Taiwanese folk medicine, the fruit bodies of A. camphorate are believed to have certain medical effects. According to the traditional way, the fruit bodies are ground into dry powder or stewed with other herbal drugs for oral uptake to treat conditions caused by poisoning, diarrhea, abdominal pain, hypertension, skin itches and liver cancer. However, no pharmacological or clinical study in these aspects has appeared in literature to date. Because of the stringent host specificity and rarity in nature, as well as the failure of artificial cultivation, xe2x80x9cniu-chang-chihxe2x80x9d is very expensive in Taiwan. In recent years, the fruit bodies of this fungus with high quality have been sold at an extremely high price of around U.S.$ 15,000 per kg.
Accordingly, there exists a need to establish a method for the large-scale cultivation of the fungus A. camphorata in a suitable artificial environment, while maintaining the pharmacological activities of the fungus A. camphorata. There also exists a need to obtain an isolate of A. camphorata that exhibits pharmaceutically useful activities when cultivated in a suitable artificial environment.
Accordingly, an object of the present invention is to provide a process suitable for culturing isolates of A. camphorata, which can grow well in the mycelial state when subjected to submerged fermentation. For this purpose, we have tested five isolates of A. camphorata collected in the Food Industry Research and Development Institute (FIRDI), Hsin-Chu, Taiwan, R.O.C. In addition, it is surprising to find that the culture of an obtained isolate exhibits a desired pharmacological activity, in particular an anti-tumor activity. According to a preferred embodiment of this invention, the carbon source of the medium, usually a carbohydrate, may be critical to obtain an optimized environment for culturing A. camphorata. 
Another object of the present invention is to provide a novel isolate of Antrodia camphorata bearing a desired pharmacological activity, in particular an anti-tumor activity, when grown in a suitable artificial environment. For this purpose, we have isolated and identified an isolate of A. camphorata, which can grow well in the mycelial state when subjected to submerged fermentation, and the resulting culture exhibits excellent pharmacological activities.
The present invention thus provides a process for producing a culture of an isolate of A. camphorata having pharmacological activity, comprising the steps of:
(a) inoculating a mycelial inoculum of an isolate of A. camphorata into a medium suitable for the growth of said isolate;
(b) cultivating the resulting culture from step (a); and
(c) harvesting the culture when the culture has a redness index a xe2x89xa73 as measured using Hunter""s coordinate system.
A still another object of the present invention is to provide a product obtained from the above process.
A further object of the present invention is to provide a pharmaceutical composition or a nutrient supplement containing a product obtained from the above process.